How to edit the contents of index.dat windows file

Question

I need to be able edit the content of index.dat file programmatically (C:\Documents and Settings\Username\Cookies\index.dat). More precisely I need to modify it in order that index.dat for one user can be used for a different user name. Is there any documentation out there for this kind of binary file?

Answer 1

The freeware code editor PSPad will allow you to view and to edit the contents of all of the index.dat files on your computer in hexadecimal form. This is done by replacing all of the digits in the first eight columns with zeros. This removes all of the information contained in the files.

It's a tedious process, requiring holding down the "0" (zero numeric key) as all of the edits are made, but anyone then accessing any of the index.dat files will get no information.

IE must be closed when doing this or you may receive an error message when attempting to save the modified file(s).

Answer 2

One method that might still work is to boot-up in safe mode and then assign yourself administrator rights and then see if you can find the files to delete them.

The method I now use is to create a batch file to rename the subfolder below the folder containing the index.bat files and to then only copy the folders back to the original location that don't contain these files but the resultant batch files needs to be run from a separate windows account that has full administrator permissions.

Answer 3

Docs will be hard to come by - Microsoft has never publicly documented the structure of the the structure of this file. That said, you can find docs on the web such as the one mentioned above. However, note that IE keeps close tabs on this file. The file is locked while IE is running (meaning, you can open/read it in some modes but not in others) and you can certainly not write to it.

Answer 4

Pasco (http://www.foundstone.com/us/resources/proddesc/pasco.htm) is a free index.dat parser that comes with the source code.